This is really interesting actually, but I do want to point out that I'm not saying all old knowledge is only of interest to historians: I was arguing against t

This is really interesting actually, but I do want to point out that I'm not saying all old knowledge is only of interest to historians: I was arguing against the idea that some old knowledge is "locked away" and not publicly available as part of some kind of conspiracy. Lots of old knowledge is readily available to the public. The complete works of Shakespeare are a good example here, as is Homer's epics The Odyssey and The Iliad. (I don't know if that TCM stuff is or not.) These kinds of things are considered "classics" and are frequently reproduced, now available online in countless places, etc. Obviously, lots of people besides historians think they're important, and so they're copied frequently and made available at large. As the famous rule goes, "99% of everything is crap", so probably all the best stuff from the past is well-preserved, and the rest, not so much. I seriously doubt that something as good as Shakespeare is locked away in someone's private library and virtually unknown to almost anyone. Of course, there's always exceptions and you never know when some overlooked tidbit of info from the distant past might be really useful, as you showed here, so I do think it's important to preserve and enable easy access to as many old works as possible.